[ic-dialog] Content shifting when vertical scroll is rendered

## Summary of the bug
Content in an `ic-dialog` shifts when a vertical scroll bar is rendered

## 🪜 How to reproduce
Tell us the steps to reproduce the problem:
1. Go to page: [Accordion with popover content](http://localhost:6006/?path=/story/web-components-accordion--with-popover-content)
2. Click on: The first `ic-accordion` in the dialog, and then the `ic-select`
3. See the message content shift

## 📸 Screenshots or code



## 🖥 📱 Device
- Type: Desktop
- Browser version: Chrome

Start with the Storybook example at `?path=/story/web-components-accordion--with-popover-content` and reproduce the shift by opening the first `ic-accordion` and then the `ic-select` in the dialog. Inspect the `ic-dialog`, `ic-accordion`, and `ic-select` components to find where rendering the vertical scrollbar changes the content position. Done means the dialog content no longer shifts in Chrome when the scrollbar appears.

Written by the indexing model from the issue text.